Narrow bandwidth operation in lte

ABSTRACT

A method of wireless communication provides narrow bandwidth operation within a wider LTE system bandwidth. Wideband information is transmitted to a first set of user equipments (UEs). Also, narrowband information is transmitted to a second set of UEs. The second set of UEs operate in a narrower bandwidth than the first set of UEs.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/612,503, entitled “Narrow Bandwidth Operation in LTE,” filed on Sep.12, 2012, which claims the benefit under 35 U.S.C. §119(e) to U.S.Provisional Patent Application No. 61/534,206, entitled “NarrowBandwidth Operation in LTE,” filed on Sep. 13, 2011, the disclosures ofwhich are expressly incorporated by reference herein in theirentireties.

BACKGROUND

1. Field

Aspects of the present disclosure relate generally to wirelesscommunication systems, and more particularly to narrow bandwidthoperation within a wider LTE (long term evolution) system bandwidth.

2. Background

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power). Examples of such multiple-access technologies includecode division multiple access (CDMA) systems, time division multipleaccess (TDMA) systems, frequency division multiple access (FDMA)systems, orthogonal frequency division multiple access (OFDMA) systems,single-carrier frequency divisional multiple access (SC-FDMA) systems,and time division synchronous code division multiple access (TD-SCDMA)systems.

These multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. An example of an emergingtelecommunication standard is Long Term Evolution (LTE). LTE is a set ofenhancements to the Universal Mobile Telecommunications System (UMTS)mobile standard promulgated by Third Generation Partnership Project(3GPP). It is designed to better support mobile broadband Internetaccess by improving spectral efficiency, lower costs, improve services,make use of new spectrum, and better integrate with other open standardsusing OFDMA on the downlink (DL), SC-FDMA on the uplink (UL), andmultiple-input multiple-output (MIMO) antenna technology. However, asthe demand for mobile broadband access continues to increase, thereexists a need for further improvements in LTE technology. Preferably,these improvements should be applicable to other multi-accesstechnologies and the telecommunication standards that employ thesetechnologies.

SUMMARY

In one aspect, a method of wireless communication is disclosed. Themethod includes transmitting wideband information to a first set of userequipments (UEs), and transmitting narrowband information to a secondset of UEs. The second set of UEs operates in a narrower bandwidth thanthe first set of UEs.

Another aspect discloses wireless communication having a memory and atleast one processor coupled to the memory. The processor(s) isconfigured to transmit wideband information to a first set of userequipments (UEs). The processor(s) is also configured to transmitnarrowband information to a second set of UEs, in which the second setof UEs operates in a narrower bandwidth than the first set of UEs.

Another aspect discloses a computer program product for wirelesscommunications in a wireless network having a non-transitorycomputer-readable medium. The computer readable medium hasnon-transitory program code recorded thereon which, when executed by theprocessor(s), causes the processor(s) to perform operations oftransmitting wideband information to a first set of user equipments(UEs). The program code also causes the processor(s) to transmitnarrowband information to a second set of UEs, in which the second setof UEs operate in a narrower bandwidth than the first set of UEs.

Another aspect discloses an apparatus for wireless communicationincluding means for transmitting wideband information to a first set ofuser equipments (UEs). The apparatus also includes means fortransmitting narrowband information to a second set of UEs. The secondset of UEs operates in a narrower bandwidth than the first set of UEs.

In another aspect, a method of wireless communication by a narrowbanddevice operating in a system including a wider bandwidth is disclosed.The method includes monitoring only a portion of the wider bandwidth.The method also includes receiving narrowband information in themonitored portion of bandwidth.

Another aspect discloses wireless communication by a narrowband deviceoperating in a system including a wider bandwidth and includes a memoryand at least one processor coupled to the memory. The processor(s) isconfigured to monitor only a portion of the wider bandwidth. Theprocessor(s) is also configured to receive narrowband information in themonitored portion of bandwidth.

Another aspect discloses a computer program product for wirelesscommunications by a narrowband device operating in a system including awider bandwidth. The computer program product has a non-transitorycomputer-readable medium. The computer readable medium hasnon-transitory program code recorded thereon which, when executed by theprocessor(s), causes the processor(s) to perform operations ofmonitoring only a portion of the wider bandwidth. The program code alsocauses the processor(s) to receive narrowband information in themonitored portion of bandwidth.

Another aspect discloses an apparatus for wireless communication by anarrowband device operating in a system including a wider bandwidth andincludes means for monitoring only a portion of the wider bandwidth. Theprogram code also causes the processor(s) to receive narrowbandinformation in the monitored portion of bandwidth.

This has outlined, rather broadly, the features and technical advantagesof the present disclosure in order that the detailed description thatfollows may be better understood. Additional features and advantages ofthe disclosure will be described below. It should be appreciated bythose skilled in the art that this disclosure may be readily utilized asa basis for modifying or designing other structures for carrying out thesame purposes of the present disclosure. It should also be realized bythose skilled in the art that such equivalent constructions do notdepart from the teachings of the disclosure as set forth in the appendedclaims. The novel features, which are believed to be characteristic ofthe disclosure, both as to its organization and method of operation,together with further objects and advantages, will be better understoodfrom the following description when considered in connection with theaccompanying figures. It is to be expressly understood, however, thateach of the figures is provided for the purpose of illustration anddescription only and is not intended as a definition of the limits ofthe present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, nature, and advantages of the present disclosure willbecome more apparent from the detailed description set forth below whentaken in conjunction with the drawings in which like referencecharacters identify correspondingly throughout.

FIG. 1 is a diagram illustrating an example of a network architecture.

FIG. 2 is a diagram illustrating an example of an access network.

FIG. 3 is a diagram illustrating an example of a downlink framestructure in LTE.

FIG. 4 is a diagram illustrating an example of an uplink frame structurein LTE.

FIG. 5 is a diagram illustrating an example of a radio protocolarchitecture for the user and control plane.

FIG. 6 is a diagram illustrating an example of an evolved Node B anduser equipment in an access network.

FIG. 7 is a block diagram conceptually illustrating a design of a basestation/eNodeB and a narrow bandwidth UE configured according to oneaspect of the present disclosure.

FIGS. 8A and 8B are diagrams conceptually illustrating narrow bandwidthoperation.

FIGS. 9A and 9B are block diagrams illustrating differentmodules/means/components in an exemplary apparatus.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with theappended drawings, is intended as a description of variousconfigurations and is not intended to represent the only configurationsin which the concepts described herein may be practiced. The detaileddescription includes specific details for the purpose of providing athorough understanding of the various concepts. However, it will beapparent to those skilled in the art that these concepts may bepracticed without these specific details. In some instances, well-knownstructures and components are shown in block diagram form in order toavoid obscuring such concepts.

Aspects of the telecommunication systems are presented with reference tovarious apparatus and methods. These apparatus and methods are describedin the following detailed description and illustrated in theaccompanying drawings by various blocks, modules, components, circuits,steps, processes, algorithms, etc. (collectively referred to as“elements”). These elements may be implemented using electronichardware, computer software, or any combination thereof. Whether suchelements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

By way of example, an element, or any portion of an element, or anycombination of elements may be implemented with a “processing system”that includes one or more processors. Examples of processors includemicroprocessors, microcontrollers, digital signal processors (DSPs),field programmable gate arrays (FPGAs), programmable logic devices(PLDs), state machines, gated logic, discrete hardware circuits, andother suitable hardware configured to perform the various functionalitydescribed throughout this disclosure. One or more processors in theprocessing system may execute software. Software shall be construedbroadly to mean instructions, instruction sets, code, code segments,program code, programs, subprograms, software modules, applications,software applications, software packages, routines, subroutines,objects, executables, threads of execution, procedures, functions, etc.,whether referred to as software, firmware, middleware, microcode,hardware description language, or otherwise.

Accordingly, in one or more exemplary embodiments, the functionsdescribed may be implemented in hardware, software, firmware, or anycombination thereof. If implemented in software, the functions may bestored on or encoded as one or more instructions or code on acomputer-readable medium. Computer-readable media includes computerstorage media. Storage media may be any available media that can beaccessed by a computer. By way of example, and not limitation, suchcomputer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer. Disk and disc, as used herein, includescompact disc (CD), laser disc, optical disc, digital versatile disc(DVD), floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

FIG. 1 is a diagram illustrating an LTE network architecture 100. TheLTE network architecture 100 may be referred to as an Evolved PacketSystem (EPS) 100. The EPS 100 may include one or more user equipment(UE) 102, an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN)104, an Evolved Packet Core (EPC) 110, a Home Subscriber Server (HSS)120, and an Operator's IP Services 122. The EPS can interconnect withother access networks, but for simplicity those entities/interfaces arenot shown. As shown, the EPS provides packet-switched services, however,as those skilled in the art will readily appreciate, the variousconcepts presented throughout this disclosure may be extended tonetworks providing circuit-switched services.

The E-UTRAN includes the evolved Node B (eNodeB) 106 and other eNodeBs108. The eNodeB 106 provides user and control plane protocolterminations toward the UE 102. The eNodeB 106 may be connected to theother eNodeBs 108 via a backhaul (e.g., an X2 interface). The eNodeB 106may also be referred to as a base station, a base transceiver station, aradio base station, a radio transceiver, a transceiver function, a basicservice set (BSS), an extended service set (ESS), or some other suitableterminology. The eNodeB 106 provides an access point to the EPC 110 fora UE 102. Examples of UEs 102 include a cellular phone, a smart phone, asession initiation protocol (SIP) phone, a laptop, a personal digitalassistant (PDA), a satellite radio, a global positioning system, amultimedia device, a video device, a digital audio player (e.g., MP3player), a camera, a game console, or any other similar functioningdevice. The UE 102 may also be referred to by those skilled in the artas a mobile station, a subscriber station, a mobile unit, a subscriberunit, a wireless unit, a remote unit, a mobile device, a wirelessdevice, a wireless communications device, a remote device, a mobilesubscriber station, an access terminal, a mobile terminal, a wirelessterminal, a remote terminal, a handset, a user agent, a mobile client, aclient, or some other suitable terminology.

The eNodeB 106 is connected to the EPC 110 via, e.g., an 51 interface.The EPC 110 includes a Mobility Management Entity (MME) 112, other MMEs114, a Serving Gateway 116, and a Packet Data Network (PDN) Gateway 118.The MME 112 is the control node that processes the signaling between theUE 102 and the EPC 110. Generally, the MME 112 provides bearer andconnection management. All user IP packets are transferred through theServing Gateway 116, which itself is connected to the PDN Gateway 118.The PDN Gateway 118 provides UE IP address allocation as well as otherfunctions. The PDN Gateway 118 is connected to the Operator's IPServices 122. The Operator's IP Services 122 may include the Internet,the Intranet, an IP Multimedia Subsystem (IMS), and a PS StreamingService (PSS).

FIG. 2 is a diagram illustrating an example of an access network 200 inan LTE network architecture. In this example, the access network 200 isdivided into a number of cellular regions (cells) 202. One or more lowerpower class eNodeBs 208 may have cellular regions 210 that overlap withone or more of the cells 202. The lower power class eNodeB 208 may be aremote radio head (RRH), a femto cell (e.g., home eNodeB (HeNodeB)),pico cell, or micro cell. The macro eNodeBs 204 are each assigned to arespective cell 202 and are configured to provide an access point to theEPC 110 for all the UEs 206 in the cells 202. There is no centralizedcontroller in this example of an access network 200, but a centralizedcontroller may be used in alternative configurations. The eNodeBs 204are responsible for all radio related functions including radio bearercontrol, admission control, mobility control, scheduling, security, andconnectivity to the serving gateway 116.

The modulation and multiple access scheme employed by the access network200 may vary depending on the particular telecommunications standardbeing deployed. In LTE applications, OFDM is used on the downlink andSC-FDMA is used on the uplink to support both frequency divisionduplexing (FDD) and time division duplexing (TDD). As those skilled inthe art will readily appreciate from the detailed description to follow,the various concepts presented herein are well suited for LTEapplications. However, these concepts may be readily extended to othertelecommunication standards employing other modulation and multipleaccess techniques. By way of example, these concepts may be extended toEvolution-Data Optimized (EV-DO) or Ultra Mobile Broadband (UMB). EV-DOand UMB are air interface standards promulgated by the 3rd GenerationPartnership Project 2 (3GPP2) as part of the CDMA2000 family ofstandards and employs CDMA to provide broadband Internet access tomobile stations. These concepts may also be extended to UniversalTerrestrial Radio Access (UTRA) employing Wideband-CDMA (W-CDMA) andother variants of CDMA, such as TD-SCDMA; Global System for MobileCommunications (GSM) employing TDMA; and Evolved UTRA (E-UTRA), UltraMobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, and Flash-OFDM employing OFDMA. UTRA, E-UTRA, UMTS, LTE and GSMare described in documents from the 3GPP organization. CDMA2000 and UMBare described in documents from the 3GPP2 organization. The actualwireless communication standard and the multiple access technologyemployed will depend on the specific application and the overall designconstraints imposed on the system.

The eNodeBs 204 may have multiple antennas supporting MIMO technology.The use of MIMO technology enables the eNodeBs 204 to exploit thespatial domain to support spatial multiplexing, beamforming, andtransmit diversity. Spatial multiplexing may be used to transmitdifferent streams of data simultaneously on the same frequency. The datasteams may be transmitted to a single UE 206 to increase the data rateor to multiple UEs 206 to increase the overall system capacity. This isachieved by spatially precoding each data stream (i.e., applying ascaling of an amplitude and a phase) and then transmitting eachspatially precoded stream through multiple transmit antennas on thedownlink. The spatially precoded data streams arrive at the UE(s) 206with different spatial signatures, which enables each of the UE(s) 206to recover the one or more data streams destined for that UE 206. On theuplink, each UE 206 transmits a spatially precoded data stream, whichenables the eNodeB 204 to identify the source of each spatially precodeddata stream.

Spatial multiplexing is generally used when channel conditions are good.When channel conditions are less favorable, beamforming may be used tofocus the transmission energy in one or more directions. This may beachieved by spatially precoding the data for transmission throughmultiple antennas. To achieve good coverage at the edges of the cell, asingle stream beamforming transmission may be used in combination withtransmit diversity.

In the detailed description that follows, various aspects of an accessnetwork will be described with reference to a MIMO system supportingOFDM on the downlink. OFDM is a spread-spectrum technique that modulatesdata over a number of subcarriers within an OFDM symbol. The subcarriersare spaced apart at precise frequencies. The spacing provides“orthogonality” that enables a receiver to recover the data from thesubcarriers. In the time domain, a guard interval (e.g., cyclic prefix)may be added to each OFDM symbol to combat inter-OFDM-symbolinterference. The uplink may use SC-FDMA in the form of a DFT-spreadOFDM signal to compensate for high peak-to-average power ratio (PAPR).

FIG. 3 is a diagram 300 illustrating an example of a downlink framestructure in LTE. A frame (10 ms) may be divided into 10 equally sizedsub-frames. Each sub-frame may include two consecutive time slots. Aresource grid may be used to represent two time slots, each time slotincluding a resource block. The resource grid is divided into multipleresource elements. In LTE, a resource block contains 12 consecutivesubcarriers in the frequency domain and, for a normal cyclic prefix ineach OFDM symbol, 7 consecutive OFDM symbols in the time domain, or 84resource elements. For an extended cyclic prefix, a resource blockcontains 6 consecutive OFDM symbols in the time domain and has 72resource elements. Some of the resource elements, as indicated as R 302,304, include downlink reference signals (DL-RS). The DL-RS includeCell-specific RS (CRS) (also sometimes called common RS) 302 andUE-specific RS (UE-RS) 304. UE-RS 304 are transmitted only on theresource blocks upon which the corresponding physical downlink sharedchannel (PDSCH) is mapped. The number of bits carried by each resourceelement depends on the modulation scheme. Thus, the more resource blocksthat a UE receives and the higher the modulation scheme, the higher thedata rate for the UE.

FIG. 4 is a diagram 400 illustrating an example of an uplink framestructure in LTE. The available resource blocks for the uplink may bepartitioned into a data section and a control section. The controlsection may be formed at the two edges of the system bandwidth and mayhave a configurable size. The resource blocks in the control section maybe assigned to UEs for transmission of control information. The datasection may include all resource blocks not included in the controlsection. The uplink frame structure results in the data sectionincluding contiguous subcarriers, which may allow a single UE to beassigned all of the contiguous subcarriers in the data section.

A UE may be assigned resource blocks 410 a, 410 b in the control sectionto transmit control information to an eNodeB. The UE may also beassigned resource blocks 420 a, 420 b in the data section to transmitdata to the eNodeB. The UE may transmit control information in aphysical uplink control channel (PUCCH) on the assigned resource blocksin the control section. The UE may transmit only data or both data andcontrol information in a physical uplink shared channel (PUSCH) on theassigned resource blocks in the data section. An uplink transmission mayspan both slots of a subframe and may hop across frequency.

A set of resource blocks may be used to perform initial system accessand achieve uplink synchronization in a physical random access channel(PRACH) 430. The PRACH 430 carries a random sequence and cannot carryany uplink data/signaling. Each random access preamble occupies abandwidth corresponding to six consecutive resource blocks. The startingfrequency is specified by the network. That is, the transmission of therandom access preamble is restricted to certain time and frequencyresources. There is no frequency hopping for the PRACH. The PRACHattempt is carried in a single subframe (1 ms) or in a sequence of fewcontiguous subframes and a UE can make only a single PRACH attempt perframe (10 ms).

FIG. 5 is a diagram 500 illustrating an example of a radio protocolarchitecture for the user and control planes in LTE. The radio protocolarchitecture for the UE and the eNodeB is shown with three layers: Layer1, Layer 2, and Layer 3. Layer 1 (L1 layer) is the lowest layer andimplements various physical layer signal processing functions. The L1layer will be referred to herein as the physical layer 506. Layer 2 (L2layer) 508 is above the physical layer 506 and is responsible for thelink between the UE and eNodeB over the physical layer 506.

In the user plane, the L2 layer 508 includes a media access control(MAC) sublayer 510, a radio link control (RLC) sublayer 512, and apacket data convergence protocol (PDCP) 514 sublayer, which areterminated at the eNodeB on the network side. Although not shown, the UEmay have several upper layers above the L2 layer 508 including a networklayer (e.g., IP layer) that is terminated at the PDN gateway 118 on thenetwork side, and an application layer that is terminated at the otherend of the connection (e.g., far end UE, server, etc.).

The PDCP sublayer 514 provides multiplexing between different radiobearers and logical channels. The PDCP sublayer 514 also provides headercompression for upper layer data packets to reduce radio transmissionoverhead, security by ciphering the data packets, and handover supportfor UEs between eNodeBs. The RLC sublayer 512 provides segmentation andreassembly of upper layer data packets, retransmission of lost datapackets, and reordering of data packets to compensate for out-of-orderreception due to hybrid automatic repeat request (HARQ). The MACsublayer 510 provides multiplexing between logical and transportchannels. The MAC sublayer 510 is also responsible for allocating thevarious radio resources (e.g., resource blocks) in one cell among theUEs. The MAC sublayer 510 is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE andeNodeB is substantially the same for the physical layer 506 and the L2layer 508 with the exception that there is no header compressionfunction for the control plane. The control plane also includes a radioresource control (RRC) sublayer 516 in Layer 3 (L3 layer). The RRCsublayer 516 is responsible for obtaining radio resources (i.e., radiobearers) and for configuring the lower layers using RRC signalingbetween the eNodeB and the UE.

FIG. 6 is a block diagram of an eNodeB 610 in communication with a UE650 in an access network. In the downlink, upper layer packets from thecore network are provided to a controller/processor 675. Thecontroller/processor 675 implements the functionality of the L2 layer.In the downlink, the controller/processor 675 provides headercompression, ciphering, packet segmentation and reordering, multiplexingbetween logical and transport channels, and radio resource allocationsto the UE 650 based on various priority metrics. Thecontroller/processor 675 is also responsible for HARQ operations,retransmission of lost packets, and signaling to the UE 650.

The TX processor 616 implements various signal processing functions forthe L1 layer (i.e., physical layer). The signal processing functionsincludes coding and interleaving to facilitate forward error correction(FEC) at the UE 650 and mapping to signal constellations based onvarious modulation schemes (e.g., binary phase-shift keying (BPSK),quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK),M-quadrature amplitude modulation (M-QAM)). The coded and modulatedsymbols are then split into parallel streams. Each stream is then mappedto an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot)in the time and/or frequency domain, and then combined together using anInverse Fast Fourier Transform (IFFT) to produce a physical channelcarrying a time domain OFDM symbol stream. The OFDM stream is spatiallyprecoded to produce multiple spatial streams. Channel estimates from achannel estimator 674 may be used to determine the coding and modulationscheme, as well as for spatial processing. The channel estimate may bederived from a reference signal and/or channel condition feedbacktransmitted by the UE 650. Each spatial stream is then provided to adifferent antenna 620 via a separate transmitter 618TX. Each transmitter618TX modulates an RF carrier with a respective spatial stream fortransmission.

At the UE 650, each receiver 654RX receives a signal through itsrespective antenna 652. Each receiver 654RX recovers informationmodulated onto an RF carrier and provides the information to thereceiver (RX) processor 656. The RX processor 656 implements varioussignal processing functions of the L1 layer. The RX processor 656performs spatial processing on the information to recover any spatialstreams destined for the UE 650. If multiple spatial streams aredestined for the UE 650, they may be combined by the RX processor 656into a single OFDM symbol stream. The RX processor 656 then converts theOFDM symbol stream from the time-domain to the frequency domain using aFast Fourier Transform (FFT). The frequency domain signal comprises aseparate OFDM symbol stream for each subcarrier of the OFDM signal. Thesymbols on each subcarrier, and the reference signal, is recovered anddemodulated by determining the most likely signal constellation pointstransmitted by the eNodeB 610. These soft decisions may be based onchannel estimates computed by the channel estimator 658. The softdecisions are then decoded and deinterleaved to recover the data andcontrol signals that were originally transmitted by the eNodeB 610 onthe physical channel. The data and control signals are then provided tothe controller/processor 659.

The controller/processor 659 implements the L2 layer. Thecontroller/processor can be associated with a memory 660 that storesprogram codes and data. The memory 660 may be referred to as acomputer-readable medium. In the uplink, the controller/processor 659provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, control signal processingto recover upper layer packets from the core network. The upper layerpackets are then provided to a data sink 662, which represents all theprotocol layers above the L2 layer. Various control signals may also beprovided to the data sink 662 for L3 processing. Thecontroller/processor 659 is also responsible for error detection usingan acknowledgement (ACK) and/or negative acknowledgement (NACK) protocolto support HARQ operations.

In the uplink, a data source 667 is used to provide upper layer packetsto the controller/processor 659. The data source 667 represents allprotocol layers above the L2 layer. Similar to the functionalitydescribed in connection with the downlink transmission by the eNodeB610, the controller/processor 659 implements the L2 layer for the userplane and the control plane by providing header compression, ciphering,packet segmentation and reordering, and multiplexing between logical andtransport channels based on radio resource allocations by the eNodeB610. The controller/processor 659 is also responsible for HARQoperations, retransmission of lost packets, and signaling to the eNodeB610.

Channel estimates derived by a channel estimator 658 from a referencesignal or feedback transmitted by the eNodeB 610 may be used by the TXprocessor 668 to select the appropriate coding and modulation schemes,and to facilitate spatial processing. The spatial streams generated bythe TX processor 668 are provided to different antenna 652 via separatetransmitters 654TX. Each transmitter 654TX modulates an RF carrier witha respective spatial stream for transmission.

The uplink transmission is processed at the eNodeB 610 in a mannersimilar to that described in connection with the receiver function atthe UE 650. Each receiver 618RX receives a signal through its respectiveantenna 620. Each receiver 618RX recovers information modulated onto anRF carrier and provides the information to a RX processor 670. The RXprocessor 670 may implement the L1 layer.

The controller/processor 675 implements the L2 layer. Thecontroller/processor 675 can be associated with a memory 676 that storesprogram codes and data. The memory 676 may be referred to as acomputer-readable medium. In the uplink, the control/processor 675provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, control signal processingto recover upper layer packets from the UE 650. Upper layer packets fromthe controller/processor 675 may be provided to the core network. Thecontroller/processor 675 is also responsible for error detection usingan ACK and/or NACK protocol to support HARQ operations.

Narrow Bandwidth Operation in LTE

One aspect of the present disclosure includes narrow bandwidth operationof a device within a wider LTE system bandwidth. In particular, thisincludes configuring the network in a way to support a class of devicesthat are only capable of narrow bandwidth transmission and receptionwith the goal to enable low cost implementations. In one configuration,the narrowband UEs coexist with other full bandwidth LTE UEs within thesame frequency band, without creating legacy issues other than the factthat the system bandwidth is shared among the two types of UEs: regularand narrow-bandwidth UEs.

One aspect enables low-data rate support in LTE (e.g., VoIP) withoutsampling and processing an entire wideband channel. In particular, oneaspect provides a low cost UE or terminal configured to operate within,for example, the Release 8, 9 and/or 10 specifications as alreadydefined. FIG. 7 illustrates a narrow bandwidth operation where B1 is thenarrow bandwidth used by the narrow bandwidth UE, B0 is the legacy LTEbandwidth and B is the effective composite legacy and non-legacybandwidth. It will be appreciated that the terms narrow bandwidth UE andlow cost LTE are used interchangeably.

One aspect is directed to enabling single-mode LTE, low-cost UEterminals. For example, in one configuration, lower layers of theprotocol stack may include narrow-band sampling for transmission andreception of a low-cost UE (possibly with a lower limit of, e.g., 6resource blocks). The low cost UE may receive existing PSS/SSS/PBCHsignals as they span 6 (six) resource blocks (RBs). Common referencesignals (CRS) that span the entire system bandwidth are processed by thelow-cost UE only for the narrow bandwidth operation. The channel stateinformation reference signal (CSI-RS), which spans the entire systembandwidth, may be processed by the low-cost UE for the narrow bandwidthoperation (using enough samples to provide meaningful information) orskipped altogether. The CSI-RS was introduced in Release 10 as the pilotsignal to be used for CSI estimation at the UE for multiple antennaports in the serving cell and possibly in non-serving cells (e.g., toenable coordinated multipoint (CoMP) feedback).

In one aspect, the PCFICH/PHICH/PDCCH signals, which span the entiresystem bandwidth, are not processed by a low-cost UE, (i.e., the signalsare skipped) in one configuration. The eNodeB, however, localizes thephysical downlink shared channel (PDSCH) in frequency and configures itto span a narrow bandwidth. For example, the eNodeB may disableintra-subframe hopping to avoid re-tuning the center frequency at slotboundaries within a subframe, and inter-subframe hopping may be disabledby the eNodeB to avoid re-tuning the center frequency across subframes,thereby maintaining the transmissions within the narrow bandwidth.

In another aspect, the UE transmission is also altered for the narrowbandwidth UEs. For example, although the physical random access channel(PRACH) is not modified (as it spans only 6 (six) resource blocks), thephysical uplink shared channel (PUSCH) is localized in frequency andconfigured to span a narrow bandwidth. In particular, intra-subframehopping may be disabled to avoid re-tuning the center frequency at slotboundaries within a subframe and inter-subframe hopping may be disabledto avoid re-tuning the center frequency across subframes.

The physical uplink control channel (PUCCH) is also localized infrequency (e.g., hopping is disabled at slot boundaries to avoidretuning to a different carrier frequency within a subframe). The UE maytransmit the sounding reference signal (SRS) over a configurablebandwidth with the exception of reciprocity based scheduling on thedownlink (for TDD operation). The narrowband UE transmission coexistswith regular LTE operation using the entire available system bandwidth.In another configuration, processing complexity is reduced for thenarrow bandwidth UE transmissions.

The higher layers may be modified to include simplification of thesystem information structure, such as, for example, the number of systeminformation blocks (SIBs). Moreover, the content of the SIBs can includeinformation indicating usage for a narrow bandwidth subsystem. In oneconfiguration, the system information is duplicated, (i.e., transmittedfor narrow bandwidth operation on top of the existing SIBs) or reusedfor narrow bandwidth operation, losing frequency diversity.

Various procedures may be implemented in narrow bandwidth operation. Theprocedures may be directed to acquisition of a physical cell ID (forSIB1), broadcast control, idle mode camping, access, connected modecamping, downlink control, uplink control, transmission modes fordownlink data and uplink data, power control, reports, HARQ operation,measurements and duplexing options. Examples of various implementationsare described below.

In full bandwidth, the acquisition of the physical cell ID (PCI) isbased on detection of PSS/SSS signals, which have a structure of sixresource blocks (RBs) transmitted at the center of the transmissionbandwidth. In a low-cost UE configured for narrow bandwidthtransmission, the PSS/SSS structure for physical cell ID (PCI) detectionis reused for narrow-bandwidth operation. The transmission of masterinformation blocks (MIB) through the physical broadcast channel (PBCH)may be done using the six middle resource block structure and,therefore, is readily available for reuse for narrow-bandwidthoperation. In full bandwidth operation, once the physical cell ID andmaster information blocks are detected, the UE is set to detect SIB-1scheduled via a regular PDCCH transmission. The sequence of: PCI(PSS/SSS)-MIB (PBCH)-SIB1 (PDCCH/PDSCH)-SIBs and Paging (PDCCH/PDSCH) isnot used for narrow-bandwidth operation because the legacy PDCCH spansthe entire downlink transmission bandwidth and because SIB-1 can beplaced arbitrarily in frequency (on subframe 5).

For narrow bandwidth operation, PDCCH-less scheduling of SIB1 may beimplemented. To bypass the detection of PDCCH, the PDSCH carrying SIB1is transmitted in a known set of resource blocks (not exceeding 6 RBs ifthe narrowband system is so limited) and at a known modulating andcoding scheme (MCS). In an alternate configuration for narrow bandwidthoperation, E-PDCCH-like scheduling of SIB1 is implemented. Theterm“E-PDCCH-like” refers to control transmissions on the data region ofthe subframe, which may resemble the E-PDCCH for relaying operation fromthe point of view of resource utilization (FDM/TDM). In particular, alow-cost UE runs blind decodes for E-PDCCH like transmissions startingon the fourth or fifth OFDM symbol in a given subframe to check forscheduling of SIB1. The SIB1 for narrow bandwidth operation may be thesame as a legacy operation (where both PDCCH and E-PDCCH point to thesame PDSCH) or a different one (possibly consolidated with other systeminformation) and transmitted less often. In another configuration, thenarrow bandwidth operation is linked to other low-cost features such asconvolutional coding support only (e.g., includes no turbo codes), wherethe transmission of all system information (SI) is duplicated.

Various procedures related to broadcast control (e.g., all systeminformation blocks (SIBs), not just SIB1 as discussed above) may beimplemented in narrow bandwidth operation. For full bandwidth operation,the system information blocks (SIBs) are scheduled via PDCCH andtransmitted on PDSCH where the transmission of PDCCH spans the entiredownlink transmission bandwidth. For narrow bandwidth operation, thelocalized transmissions in frequency for the control channel schedulingSIBs and for PDSCH occur. In particular, in one configurationoverloading is implemented where assignments with E-PDCCH-like controland single PDSCH transmission are shared between regular and narrowbandwidth capable UEs. The narrow bandwidth capable UEs and fullbandwidth capable UEs look to the same data region, although the regularUEs look at the entire bandwidth. Additionally, in another configurationfor narrow bandwidth operation, E-PDCCH-like control is used where thesystem information relevant for narrow bandwidth operation istransmitted in a form of streamlined SIBs transmitted with lessfrequency than for the regular system.

For full bandwidth operations, when in idle mode, the UE reads PDCCHlooking for the PI-RNTI (paging information-radio network temporaryidentifier) for possible pages followed by data allocations in PDSCH.For narrow bandwidth operation, PDCCH-less scheduling of pages may beimplemented. In this configuration, PDSCH is transmitted carrying pagesin a known set of resource blocks (e.g., not exceeding 6 RBs) and at aknown modulation and coding scheme (MCS). In an alternate configurationfor narrow bandwidth operation, E-PDCCH like scheduling of pagingmessages is implemented in corresponding subframes. The paging ofregular UEs and narrow bandwidth UEs can be separated. For idle modeoperation, narrow bandwidth UEs may camp in the same frequency location,(e.g., the 6 resource blocks in the middle of the band). If pagingcapacity is at issue, multiple narrow bandwidth carriers may beconfigured within the same legacy transmission bandwidth to enableindependent paging at each carrier.

Various procedures related to access may be implemented in narrowbandwidth operation. For full bandwidth UEs, the initial access is basedon the physical random access channel (PRACH), which spans six (6)resource blocks. The location in time and frequency of PRACH signalingis set by higher layers (e.g., set in frequency at the edge of theuplink transmission bandwidth to avoid fragmentation of datatransmissions). For narrow bandwidth operation, the location of PRACHopportunities can similarly be identified (i.e., via the detection ofSIBs discussed above). This type of setting may use flexible duplexingseparation between downlink and uplink central frequencies so that thesix resource blocks for downlink reception (of pages) and the sixresource blocks for uplink transmission (of PRACH) can be at multipleplaces. Alternatively, the PRACH center frequency may be set in themiddle of the uplink carrier frequency.

Various procedures related to connected mode camping may be implementedin narrow bandwidth operation. In connected mode, the full bandwidthoperable UE has a downlink center frequency for reception and an uplinkcenter frequency for transmission in accordance with operation in theassigned frequency band. The sampling at reception and transmissionoccurs in accordance with the downlink and uplink system bandwidths,respectively so that allocations can be partial in frequency but withoutlimitations about location within the downlink/uplink transmissionbandwidths. For narrow bandwidth operation, the frequency location ofthe resource blocks of downlink reception and uplink transmission, arenot necessarily in the center of the band as illustrated in FIG. 7.Rather, the resource blocks for the narrow operation bandwidth may beplaced anywhere in the band. In one configuration, the narrow bandwidthregion includes six resource blocks positioned in any location withinthe narrow operation band. The capability to place differentnarrow-bandwidth UEs on different resource blocks enables multiplexingin the frequency domain for these UEs within a given subframe. Higherlayer signaling indicates the transmission/reception center frequenciesto the narrow bandwidth UEs.

In narrow bandwidth operation, various procedures may be implementedthat relate to downlink control, such as physical control formatindictor channel (PCFICH), physical hybrid ARQ indicator channel(PHICH), and physical downlink control channel (PDCCH). PCFICH indicatesthe control span in number of orthogonal frequency division multiplexing(OFDM) symbols for the corresponding subframe. In one configuration ofnarrow bandwidth operation, PCFICH is not used. The starting OFDM symbolfor data/E-PDCCH transmissions for narrow bandwidth operation can be:fixed (e.g., 4th OFDM symbol); semi-statically configured (e.g. by PBCHor some other SIB to be able to exploit some extra OFDM symbol for theeffective data region for narrow bandwidth transmissions in thedownlink); and/or dynamically configured (e.g., conveyed within theE-PDCCH/E-PHICH structure to indicate the first symbol for the data(PDSCH) transmission for narrow bandwidth UEs).

PHICH carries downlink acknowledgements (ACKs) and in one configurationfor narrow bandwidth operation, the downlink ACK is eliminated.Scheduled retransmissions are instead relied upon or, optionally, HARQoperation is removed for narrow bandwidth operation. In an alternateconfiguration, an E-PHICH-like structure is implemented in the dataregion. In one example, the E-PDCCH structure may be reused.

PDCCH carries downlink assignments, uplink assignments, and powercontrol commands. For narrow bandwidth operation, an E-PDCCH-likestructure may be implemented, where E-PDCCH is reused. Alternately, inanother configuration, a preamble based structure (as part of PDSCH) isimplemented. In one example, this is similar to Ev-DO (evolution fordata optimized), where downlink assignments may be eliminated. Thescrambling may be based on the UE ID (C-RNTI) for PDSCH and PDSCH blinddecoding is performed for a limited set of MCSs (similar toHS-SCCH-(high speed shared control channel)-less operation in HSPA (highspeed packet access)). For uplink assignments, an uplink grant is used.Narrow bandwidth operation may use medium access control (MAC) protocoldata unit (PDU) based assignments (inside PDSCH). Additionally,semi-persistent scheduling (SPS) with overloading of multiple UEs may beused.

Aggregation levels may be limited or absent. Further, modulation andcoding scheme (MCS) signaling may be limited. In some configurations fornarrow bandwidth operation, limited blind decodes may be implemented.Additionally, the resource allocation field may be limited or absent.The granularity of resource allocation (currently one resource block)and cyclic redundancy check (CRC) may each be re-assessed for narrowbandwidth operation.

Various procedures related to uplink control may be implemented innarrow bandwidth operation. In full bandwidth operation, the physicaluplink control channel (PUCCH) has the inherent property to hop at theslot boundaries within a subframe. In Release 10, LTE defines PUCCHformat 0 as carrying scheduling requests (SRs). The PUCCH format 1a/1bis defined to carry 1-2 bits of uplink ACK. The PUCCH format 2/2a/2b isdefined to carry channel state information (CSI), (e.g., channel qualityindex (CQI), precoding matrix indicator (PMI), and rank indicator (RI))possibly in conjunction with uplink ACK (for PUCCH format 2a/2b). ThePUCCH format 3 is defined for multi-bit ACK transmission in carrieraggregation scenarios and TDD.

In one configuration for uplink operation in a narrow bandwidth,existing formats are reused without hopping at slot boundaries.Moreover, the set of PUCCH formats that are supported for low-costnarrow bandwidth UEs may be limited. In one example configuration, thePUCCH format 0 is used for scheduling requests (SRs). Alternately,uplink resources can be accessed through the random access controlchannel (RACH) and format 0 is not supported.

The PUCCH format 1a/1b may be used for transmission of uplink ACK bits,which, in turn, are results of HARQ operation on the downlink. If HARQoperation is not supported in the downlink by narrow bandwidth UEs, thisformat is not used. If downlink HARQ operation is supported (e.g., toimprove the downlink coverage of data transmissions), then, in oneaspect, a format is supported that conveys ACK bits on the uplink. Forexample, transmission of uplink ACK bits can be performed by reusing theexisting PUCCH format 1a/1b, or, alternately a mechanism may be utilizedto convey ACK bits on the uplink.

The PUCCH format 2 provides the periodic CSI feedback mechanism and isrelevant for downlink HARQ operation and downlink power control. In oneconfiguration, this UE feedback is not frequent for narrow bandwidth UEs(which may be static devices). Optionally, in another configurationPUCCH format 2 is not supported for narrow bandwidth operation andinstead an aperiodic CQI mechanism is used. Additionally, in oneconfiguration for low cost narrow bandwidth operation, PCCH format 3 isnot used.

In another configuration for uplink operation in a narrow bandwidth,CDMA based uplink control is implemented. The CDMA based uplink controlmay be implemented because the overhead from PUCCH transmissions on anarrow bandwidth system (e.g., one with. 6 RBs) scale very coarsely (inmultiples of 16.66%). To achieve better granularity, several PUCCH canbe multiplexed on the same resource block in CDMA where each PUCCHchannel is spread by its unique PN (pseudo noise) sequence.

In one aspect, scheduling requests are done via RACH and CSI feedback isperformed via regular PUSCH. The existing PUCCH format 1a/1b can then bereused. In one aspect, 1a is reused because the downlink MIMO may not besupported by all low cost UEs. Alternately, in another aspect, a newmechanism is utilized to convey ACK bits on the uplink.

Various procedures related to downlink data transmission modes anduplink data transmission modes may be implemented in narrow bandwidthoperation. In particular, for narrow bandwidth downlink datatransmission modes, common reference signals (CRS) may be used. The CRSmay be utilized, instead of UE reference signals (RS), to eliminate theoverhead caused by UE-RS transmission. Additionally, in another aspect,the channel state information (CSI) estimation of CRS is used instead ofestimating based on CSI-RS. The CSI-RS provides one sample point foreach antenna for each resource block instead of the eight (8) samplepoints for the first two antenna ports for CRS. Therefore, the CSIfeedback may be based on CRS for narrow bandwidth UEs. In anotherconfiguration multi-user packets (e.g., like in EvDO) may be used.

For uplink data transmission modes in narrow bandwidth operation, thereis no uplink hopping operation. Additionally, there is no clustereduplink transmission and no PUCCH+PUSCH transmission.

Various procedures related to power control may be implemented in narrowbandwidth operation. In particular, transmit power control (TPC)commands for uplink power control are part of the various downlinkcontrol information (DCI) formats for downlink assignments and uplinkgrants in full bandwidth operation. This same mechanism can be used fornarrow bandwidth operation as part of the E-PDCCH structure. In otherwords, power control commands may be received in a narrowband controlchannel (e.g., E-PDCCH), instead of the full band PDCCH. Power controlfor downlink operations in narrow bandwidth may be based on CQI reportsfrom the UE (if available). In another configuration, an open loop isused for power control.

In other aspects, HARQ operation may or may not be enabled. In oneaspect, HARQ operation is disabled for the narrow bandwidth, low-cost UEoperation. Disabling HARQ may forfeit the use of a PHICH replacementand/or PUCCH format 1a/1b replacement.

Various procedures related to radio resource management (RRM) and/or RLM(radio link monitoring) measurements may be implemented in narrowbandwidth operation. In particular, the measurements of the serving cellare based on the CRS on downlink resource blocks where the UE inconnected mode is camping.

Various procedures related to duplexing options may be implemented innarrow bandwidth operation. In particular, various duplexing options maydetermine which resource blocks are used for decoding and demodulationin the downlink and for transmission on the uplink.

In full bandwidth operation, the transmission of the system informationis in one set of resource blocks to avoid duplicating the transmissionof the same system information on different parts of the band. However,for downlink data transmission (other than system information (SI)) andfor uplink data transmissions, the ability to move different UEs todifferent sets of resource blocks provides the capability to supportmore UEs and higher data rates. Thus, for narrow bandwidth UEs thesystem information can be transmitted in different sets of resourceblocks.

In a first variable duplexing option, downlink transmissions are locatedin six middle resource blocks. The uplink transmission may be locatedanywhere in the bandwidth spectrum. In a second duplexing option, forthe downlink, the SIBs in are located in six middle resource blocks andthe unicast data for connected mode UEs are located in any six resourceblocks. In this second duplexing option, the network pages UEs for thechange of information. The UEs then tune to the middle six resourceblocks. The UE search of neighbor cells may be similar tointer-frequency measurements in Release 8 (i.e., to receive PSS/SSS inthe middle 6 RBs).

In another aspect, the SIBs may be reused from legacy transmissions, ormay be newly transmitted.

In another aspect, the 1.4 MHz system may be streamlined by eliminatingthe transmission of PBCH. In one aspect, the narrow band, low-cost UEdoes not utilize PBCH (e.g., the master information block (MIB)). ThePBCH may be used to convey the system frame number (SFN). Additionally,PBCH may be utilized to convey the CRC masking by the number of CRSantenna ports. In one aspect, the number of antenna ports for a CRSoperation may be detected blindly at the UE. Alternatively, in anarrowband operation, 4 CRS ports may be assumed for downlinktransmissions in corresponding resource blocks.

In one configuration, the eNodeB 610 is configured for wirelesscommunication and is configured to transmit wideband information to afirst set of UEs (i.e., regular UEs configured to operate in a fullbandwidth range). The eNodeB 610 transmits narrowband information in anarrower bandwidth to a second set of UEs (i.e., narrow bandwidthdevices). In one aspect, the eNodeB 110 transmits via thecontroller/processor 675, transmit processor 616, transmitters 618,and/or antenna 620.

In one configuration, the narrow bandwidth UE 650 is configured tooperate in a wireless communication system having a wider bandwidth andis configured to monitor only a portion of the wider bandwidth. The UE650 receives narrowband information in the monitored portion ofbandwidth. In one aspect, the UE 650 receives via the antenna 652,receivers 654, receive processor 656, controller/processor 659 and/ormemory 660.

FIG. 8A illustrates a method 801 for operating in a narrower bandwidth.In block 810, an eNodeB transmits wideband information to a first set ofUEs. In block 812, the eNodeB transmits narrowband information to asecond set of UEs. The second set of UEs operates in a narrowerbandwidth than the first set of UEs.

FIG. 8B illustrates a method 802 for operating a narrowband device in asystem including a wider bandwidth. In block 820, the UE monitors only aportion of the wider bandwidth. In block 822, the UE receives narrowbandinformation in the monitored portion of bandwidth. FIGS. 9A and 9B arediagrams illustrating an example of a hardware implementation for anapparatus 900 employing a processing system 914. FIG. 9A illustrates anapparatus 900 a for use with an eNodeB and FIG. 9B illustrates anapparatus 900 b for use with a UE. In both FIGS. 9A and 9B, theprocessing system 914 may be implemented with a bus architecture,represented generally by the bus 924. The bus 924 may include any numberof interconnecting buses and bridges depending on the specificapplication of the processing system 914 and the overall designconstraints.

Each of the apparatus 900 a and 900 b in FIGS. 9A and 9B include aprocessing system 914 coupled to a transceiver 930. The transceiver 930is coupled to one or more antennas 920. The transceiver 930 enablescommunicating with various other apparatus over a transmission medium.The processing system 914 includes a processor 922 coupled to acomputer-readable medium 926. The processor 922 is responsible forgeneral processing, including the execution of software stored on thecomputer-readable medium 926. The software, when executed by theprocessor 922, causes the processing system 914 to perform the variousfunctions described for any particular apparatus. The computer-readablemedium 926 may also be used for storing data that is manipulated by theprocessor 922 when executing software.

In FIG. 9A, the bus 924 links together various circuits including one ormore processors and/or hardware modules, represented by the processor922, the computer-readable medium 926, and the modules 902 and 904. Thebus 924 may also link various other circuits such as timing sources,peripherals, voltage regulators, and power management circuits, whichare well known in the art, and therefore, will not be described anyfurther.

In FIG. 9A, the processing system 914 includes a module 902 fortransmitting wideband information. The processing system 914 alsoincludes a module 904 for transmitting narrowband information. Themodules may be software modules running in the processor 922,resident/stored in the computer-readable medium 926, one or morehardware modules coupled to the processor 922, or some combinationthereof. The processing system 914 may be a component of the basestation 610 and may include the memory 676 and the controller/processor675.

In FIG. 9B, the bus 924 links together various circuits including one ormore processors and/or hardware modules, represented by the processor922, the computer-readable medium 926, and the modules 932 and 934. Theprocessing system 914 includes a module 932 for monitoring only aportion of a wider bandwidth. The processing system 914 also includes amodule 934 for receiving narrowband information. The modules may besoftware modules running in the processor 922, resident/stored in thecomputer-readable medium 926, one or more hardware modules coupled tothe processor 922, or some combination thereof. The processing system914 may be a component of the UE 650 and may include the memory 660,and/or the controller/processor 659.

Those of skill would further appreciate that the various illustrativelogical blocks, modules, circuits, and algorithm steps described inconnection with the disclosure herein may be implemented as electronichardware, computer software, or combinations of both. To clearlyillustrate this interchangeability of hardware and software, variousillustrative components, blocks, modules, circuits, and steps have beendescribed above generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem. Skilled artisans may implement the described functionality invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the disclosure herein may be implemented or performedwith a general-purpose processor, a digital signal processor (DSP), anapplication specific integrated circuit (ASIC), a field programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described herein. Ageneral-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The steps of a method or algorithm described in connection with thedisclosure herein may be embodied directly in hardware, in a softwaremodule executed by a processor, or in a combination of the two. Asoftware module may reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of storage medium known in the art. Anexemplary storage medium is coupled to the processor such that theprocessor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor. The processor and the storage medium may reside in anASIC. The ASIC may reside in a user terminal In the alternative, theprocessor and the storage medium may reside as discrete components in auser terminal

In one or more exemplary designs, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Computer-readable media includes both computerstorage media and communication media including any medium thatfacilitates transfer of a computer program from one place to another. Astorage media may be any available media that can be accessed by ageneral purpose or special purpose computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code means in the form of instructions or datastructures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

The previous description of the disclosure is provided to enable anyperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the spirit or scopeof the disclosure. Thus, the disclosure is not intended to be limited tothe examples and designs described herein but is to be accorded thewidest scope consistent with the principles and novel features disclosedherein.

What is claimed is:
 1. A method of wireless communication, comprising:transmitting wideband information to a first set of user equipments(UEs); and transmitting narrowband information to a second set of UEs,in which the second set of UEs operate in a narrower bandwidth than thefirst set of UEs.